<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>4显示模式</title>
    <style>
        div{
            width: 200px;
            height: 100px;
            border: 2px solid #00f;
            display: block;/*块级元素:可以设置宽高 竖着排*/
        }
        span{
            width: 100px;
            height: 100px;
            background-color: #ff0;
            display: inline;/*行内元素:无法设置宽高 横着排 大小由内容撑起来*/
            display: block;/*模式显示可以修改*/
        }
        input,button{
            width: 100px;
            height: 100px;
            display: inline-block;/*行内块:既能设置大小,又横着排*/
        }
        .d2{
            display: none;
        }
    </style>
</head>
<body>
    <div class="d1"></div>
    <div class="d2"></div>
    <div class="d3"></div>
    <hr>
    <span>123456789</span>
    <span>123456789</span>
    <span>123456789</span>
    <hr>
    <input type="text">
    <input type="text">
    <input type="text">
    <button>我是按钮</button>
</body>
</html>